National Weather Service United States Department of Commerce

Strong to Severe Storms in the Upper Midwest; Bering Sea Low Continues to Impact Southwest Alaska

Scattered severe thunderstorms are possible Thursday across central and eastern Minnesota, Iowa, and western Wisconsin. A few tornadoes, isolated very large hail, and damaging winds may occur. In southwest Alaska, a Bering Sea low continues to cause strong winds, significant rainfall, and high seas, with further impacts expected Friday into the weekend from a North Pacific storm. Read More >

Mesoscale Discussion #0220 issued at 1921 UTC 28 March 2010
MESOSCALE DISCUSSION 0220
NWS STORM PREDICTION CENTER NORMAN OK
0221 PM CDT SUN MAR 28 2010
   
AREAS AFFECTED...PARTS OF NE GA AND UPSTATE SC INTO WRN NC
   
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 
   
VALID 281921Z - 282115Z
   
CORRECTED STATES IN HEADER
   
IT SEEMS PROBABLE THAT THE RISK FOR SEVERE STORMS WILL INCREASE LATE
THIS AFTERNOON...WITH A WATCH LIKELY BY AROUND 21Z.
   
UNCERTAINTY EXISTS CONCERNING MID-LEVEL SUBSIDENCE...JUST TO THE
SOUTH OF THE AXIS OF A 90 KT SOUTHWESTERLY 500 MB JET STREAK NOSING
NORTHEASTWARD TO THE IMMEDIATE LEE OF THE SOUTHERN APPALACHIANS...
AND ITS POTENTIAL IMPACT ON CONVECTIVE DEVELOPMENT LATE THIS
AFTERNOON...PARTICULARLY GIVEN THE LACK OF STRONGER INSTABILITY. 
BUT ONGOING DESTABILIZATION...ASSOCIATED WITH BOUNDARY LAYER HEATING
AND LOW-LEVEL THERMAL/MOISTURE ADVECTION NEAR A REMNANT FRONTAL ZONE
TO THE LEE OF THE HIGHER TERRAIN...IS CONTRIBUTING TO
INCREASING/DEEPENING CONVECTIVE DEVELOPMENT.  AS FURTHER SLOW
DESTABILIZATION PROGRESSES THIS AFTERNOON...IN THE PRESENCE OF
STRONG DEEP LAYER SHEAR...INCREASING NEW THUNDERSTORM ACTIVITY
APPEARS PROBABLE...WITH THE POTENTIAL THAT A FEW COULD BECOME
SEVERE.  RUC IS SUGGESTIVE THAT STRENGTHENING OF SOUTHERLY 850 MB
FLOW MAY OCCUR NEAR A WEAK FRONTAL WAVE ACROSS THE WESTERN CAROLINAS
BY THE 21-23Z TIME FRAME...ENLARGING CLOCKWISE CURVED LOW-LEVEL
HODOGRAPHS...AND CONTRIBUTING TO THE RISK FOR TORNADOES ...IN
ADDITION TO LARGE HAIL/LOCALIZED POTENTIALLY DAMAGING WIND GUSTS.
   
..KERR.. 03/28/2010
   
   
ATTN...WFO...CAE...GSP...MRX...FFC...
   
LAT...LON   35328368 35878251 35938178 35498111 34998079 34358141
            33898228 33788321 34088389 34618400 35328368